During this Boundless Tribulation, cultivators held the initiative. They could decide for themselves whether to sacrifice their lifespan, and how much of it to offer.
Generally speaking, anyone undergoing the Tribulation would calculate in advance how many years of lifespan they needed for their cultivation, and then sacrifice all the excess. In exchange, this made it much easier to pass the Boundless Tribulation.
After stepping into the True Immortal realm, lifespan did not increase. Unless one managed to reach the level of a Celestial Venerable, lifespan could not be extended. Whatever lifespan a tribulation-taker had left after sacrificing during this Boundless Tribulation was all they would have—it would never grow again. Unless they encountered a rare stroke of fortune, this was impossible to change.
Chapter 1203